Evaluation of Topical Gels Containing Non-Steroidal Anti-Inflammatory Drugs on Inflammation and Hyperalgesia in rats

The systemic use of non-steroidal anti-inflammatory drugs (NSAIDs) which act by inhibiting cyclooxygenase (COX) is severely hampered by gastric and peptic ulcers. The topical delivery of NSAIDs has the advantages of avoiding gastric and peptic ulcers and delivering the drug to the inflammation site. There are no studies that compared the pharmacological profile of gel formulations containing different NSAIDs. Therefore, attempt has been made to study the anti-inflammatory and antihyperalgesic effects of NIZER gel (nimesulide, a preferential COX-2 inhibitor, 1 mg per 100 mg gel) and VOVERAN Emulgel (diclofenac sodium, a nonselective COX (COX-1/2) inhibitor, 1 mg per 100 mg gel) in carrageenan-induced inflammation and hyperalgesia in rats. A 100 mg of NIZER gel or VOVERAN Emulgel when applied topically 30 min before inflammogen administration showed marked anti-inflammatory and antihyperlagesic effects against carrageenan-induced inflammation in rats with more significant effect was observed with NIZER gel. The results indicate that gels containing a preferential COX-2 inhibitor are better than a non-selective COX-1/2 inhibitor in alleviating inflammation and hyperalgesia.